Recuperator



1.1. VOLLKUMMER.

RECUPERATOH APPLICATION FILED DEC. 11, 1919.

1 ,402,325, Patented Jan. 3, 1922.

2 SHEET SHEiT I. 30 a-=+ 2. H51. K3

WITH lllll INVIIITOI 9 WWW a, r MOW THEODORE '3. VOLLKOEMER, 0FPITTSBURGH, PENNSYLVANIA.

BECUPEBATGE.

Application flied December 1:, 1919. Serial No.

To all whom it my concern:

Be it known that I, Tmsooone J. VoLLnonown, a resident 1)? Pittsburgh,in the county of Allegheny and State of Pennsylvania, have invented anew and useful Improvement in Recuperat-ors, of which the following is aspecilication.

his invention relates to mufl'le furnaces, and particularly to apparatusfor preheating air supplied to the combustion'chzunber of such-furnaces.Among the special forms of construction it is intended to proride both afurnace wall and a preheating passage for the air which will be so constructed as to withstand expansion and con traction on account ofchanges in temperature to which such'btrcctures are-subjectcd.Prcheating passages for "the air are provided directly in the path ofthe burnt gases, in the flue, and yet accessible for in spection andrepair.

eferrin to the drawings Fi 1 is a section through the furnace on line1-1 of Fig. 3- Fig. 2 is a. vertical section on line 2-2 0% Fig. 1; Fig.3 is a. vertical cross-section on the line 3-3 of Fig. and Fig. 4 is avertical section on the line 4-4 of Fl". 1.

ln mufiio furnaces designed for preheat ing billets or other metallicarticles, the main heating chamber is combustion chamber in which heatis generated by the burning of a. gas, or other suitable fuel. In anycase air must be supplied to support the combustion, and c. wreak dealof host may be conserved by pre leating the air before introducing it tothe coinbust-ion chnmber. This may be done bx leading the air throughpassages surrounding or leading through the combustion chamber, beforeintroducing it thereto.

The walls of a muille furnace are subjected to extreme heat, and whenthe furnace is not in use they are allowed to partially cool, therebyresulting in expansion and contraction which tends to crack the materialof which the walls are made. The construction described in the presentspecification is designed to obviate this danger, as will more full Yapp'cur hereinafter.

The furnace illustrated herein as embodying the present inventioncomprises a base 1 sectod upon foundation 2, and sup- Specillcntion ofLetters Patent.

surrounded by a porting the bottom 3 of the heating or muffie chamber,which has a. door. 4 an end well 5, and is built up of side Walls 6 and7, connected by two or more top arch members 8 and 9 resting on thesidewalls, as more fully described hereinafter. Surrounding the heatingchamber is the combustion chamber 10. which is enclosed by anintermediate wall 11, which in turn is surrounded by a space 12-, formedbetween the wall. 11 and the outer well 13 of the whole furnaceconstruction. The heating chamber has a suitable bottom preferablyformed by arched cooperatin members 14- nnd 15. t will be unclerst'o'o"that all-of thewclls of the heating chamber are made of sufficientlyrefractory material. The combustion chamber 10 extends cntirelv aroundthe heating chamber, and. is direct connected to the mixing andcombustion chamber 16, situated beneath the heating compartment.

F ucl is suoplied to the combustion and mixing chum er 16 by means ofnozzle 17, connected by pipe 18 to a. source of fuel. such as gas. oil.etc. An additional pipe 19 is connected to the nozzle for mixing andfeeding the fuels. This mny carrv air, steam, another gas, etc. Thenozzle is su ported by a casting 20 mounted under this base l of thewhole furnace structure. Controlling valves 18 and connections to thepipe 18 are located in pit 21, underneath the base of the furnace. Ahinged door 22 is provided near the nozzle to permit inspection andadjustment thereof from the outside of the furnace. Fuel is forcedthrough the nozzle 17 uncle? considerable pressure into the combustionchamber 16. which extends under and around the walls of the heatingchamber 23.

Air to be mixed with the fuel, and to support the combustion thereof isconstantly drawn by the exhaust about the nozzle 17, and also by thedrought through the main flue 24 of the furnace stack, through thepassages 25 and 26, which extend through the U-shaped preheetin members27 and 28, and thence by later-a passages 29 and 30. 31 and 32 in theside walls into the space 12, surrounding the wall 11, as shown in Fig.3. This Space 12 eater nal openings 33 and 34: ad; its my, through whichthe air is drawn.

Patented Jan. 3, 1922.

The prehoatipg tubes 2? ad 28 are form'od of r: SGIIBS of hollow tlles35, seated one noon the other, and it will be observed that thosemembers are situated in the com oan'ment 36 which is a part; ofthe fine24, lemlim out throu h stack a? of the furnaoe. lhe joints iwetwoon thetiles are all horizontal, therefore the clay therein does not fall outunder the exlgansion and contraction of the tiles,as IS the 01152 withvertical points.

Therefore air to support the combustion about tho heating clmmber-isdrawn thmugh openings 33 and 3% into the compartment 12, which oKte-nrlsaround the furnace wall 11, which in turn extends entirely around thecombustion chamber 10. Thereforp the air is exposed to tho entire heatedour-foes of fihe wall it which encloses the bummg gases. Consequent ythe air is considerably warmed in its pasmgo around said wall tooponings 30, ill and by which it is led from coropmtmeml. 2 21120 theouter ends 05 the U-shoped. passages through the member 27 and 287 inpassing through these latter mambois still further heated, since theylie entirely within the stack through which the heated Elmo gas passesin its escape from the comlmstion chamber. Air is therefore deliveredpreheated to the combustion chumhot :.-L n point justobo-se the nozzle17. The result is o z'eouperatol' of grant ofliuicncy.

The nmlringr of the U-sbaped preheating memJ-ms 27 um! '25, which aresituated rectly in the path of thehol; flue gases, of sections soatorl0111*. upon the other, permits these members to readily expand andconmm, without cracking, and without: injury to the structum. Theirposition insures the-i 1- exposure to tho maxinuu'n heat of the wastegases, which entirely surround them, and also permits their read};inspection by Knocking out the temporary wall 38, used to seal up the:opening 39, which is rovidecl in the furnace wall at the fool; of t astack. The honrml flue gases pass out of the (ombustinn chamber throughopenings 40. and come direrLlV in contact with the hum of thoseU-slmpc-rl nmmbers and pass therw umuml before going up to the fine 21.from whivh they 05mm to the atme sphom in owlor to who till't! of liloJQR'X severe sir-aim which :no imposed upon tho-walls of the llialiill}!compartment 23, that lm-mlmr it m-urvmbly made with a bottom of iwn nwhmembers l4 and 15, ha ing an interln kiri tongue nml groove at theirpoint of worm-t. uml Hl'lltfll upon base mvmhers 4! nrul of the mainfurnace construction. The Sl\l Po fox-med ln' slabs of lL l:l .i1 l'material i mu] 7. \Vhir'h 99:1? ni Choir lnufll :wnh ugmm I' l: :nirimornlml's 41 and 49, nnrl whirl: incline outu'uz'rlly, loaning ngninstentirely supports 43 built out from tho'maip wallll of the combustionchamher. Seatmg upon the tops of the side walls'fi and 7, in a grooveformed by the top of that member smiths and 01 supports 43 two curvedtop mamhers 3 and. 9 are pIOVlBd, which no joiuod. oogethor by a tongueand groove arrangement along the line of their contact. Thm it will beseen that the antire wall of the heating chamber is free to expand our}contiact, and that the parts thereof may readily adjust themselves tosuch expansion and contraction, without breakin any joints, and withoutbreaking the s ructm'e as a.

whole. This is a. very im ortantfeaturo, as

is also the oroviaion of t .e U-shapod tubes 27 and 28 of a. form whichpermits free expansion and contraction without breaking.

I claim:

1. In a recuperativo {u mace constmction a preheating passage forsupplying air to the combustion chamlroz, said passage loading .arouml'the walls of the combustion chamber nncithrcugh a conduit situated inthe furnace stack. I

2. In a furnace construction moans for preheating air supplied to thecombustion chamber, said means comprising vertical air conduitsarranged. entirely inside the furnace stack in the path of the gases ofcombustion.

3. In a reouperative furnace oonstmc'tion the provision of ahconduitssituotod in the path of the gases of combustion, said con (halts beingformed of independent sections seated one upon another.

4. In 21. recuperat iverfuroaoe construction conduits for supplying airto the combustion chamber, said conduits com rising inverted U-shapodhollow tile memEers seated on the bottom of the furnace stack and freelyexposed to the heat of the escaping gases.

In a mufile furnace construction a neating chamber having its wallsformed of slabs of refractory material seating loosely one upon theother and held in position by gravity.

6. In mulllo furnace construction 9. heating chamber having its sidewalls formed by loosely mounted slabs standing on edge and inulinc-(ioutwardly, and its top formed by nt'ch members seated u n the top of thoside members, and lied in' position by gravity.

7. In a muilio fIHHRCGCOUSiZIUCtlOH a heat ing chamber having its sidewalls formed from slabs of refractory material seated upon edge andinvlinod outwardly against supports from the side walls of thecombuslion Pil=llfll10l'. and :1 top from the heating: \lmmlc-l'composed of slab members seated loosc-lv upon the tops of the sidemembers, -lwmhy t hermit free expansion and con' imvtion of the. wallsof the heating chamber,

S. In a furnace construction, air oonduits ciated setions withhorizontal joints theresituated in the path of the gases of conibetween.10 bustion. said conduits being formed by in- In testimony whereof Ihave hereunto set dependent horizontal hollow sections seated my hand. 5one upon the other.

9. In a furnace construction, air conduits 1HEODQR'P VGLLKOMMER situatedin the path of the ases of combus- Witness: 7

tion, said conduits being ormed of 2350- Amen A. Tim.

